Serial recall of visuospatial and verbal information with and without material-specific interference: Implications for contemporary models of working memory

Abstract

A longstanding question in working memory (WM) research concerns the fractionation of verbal and nonverbal processing. Although some contemporary models include both domain-specific and general-purpose mechanisms, the necessity to postulate differential processing of verbal and nonverbal material remains unclear. In the present two-experiment series we revisit the order reconstruction paradigm that Jones, Farrand, Stuart, and Morris (1995) used to support a unitary model of WM. Goals were to assess (1) whether serial position curves for dot positions differ from curves for letter names; and (2) whether selective interference can be demonstrated. Although we replicated Jones et al.'s finding of similar serial position curves for the two tasks, this similarity could reflect the demands of the order reconstruction paradigm rather than undifferentiated processing of verbal and nonverbal stimuli. Both generalised and material-specific interference was found, which can be attributed to competition between primary and secondary tasks for attentional resources. As performance levels for the combined primary and secondary tasks exceed active WM capacity limits, primary task items apparently are removed from active memory during processing of the secondary list and held temporarily in maintenance storage. We conclude that active WM is multimodal but maintenance stores may be domain specific.

Keywords:

• Serial memory
• Working memory
• Short-term memory
• Recognition memory
• Order reconstruction

Lynne C. Davis is now at the Brain Injury Research Center, TIRR Memorial Hermann, Houston, TX. Shruti Rane is now at the Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD. This manuscript is based on the doctoral dissertation of Lynne C. Davis and master's thesis of Shruti Rane under the supervision of Merrill Hiscock. The authors wish to thank Bruno Breitmeyer, Paul Cirino, Paul Massman, and Michael Watkins for their contributions to the manuscript as dissertation and thesis committee members.

Lynne C. Davis is now at the Brain Injury Research Center, TIRR Memorial Hermann, Houston, TX. Shruti Rane is now at the Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD. This manuscript is based on the doctoral dissertation of Lynne C. Davis and master's thesis of Shruti Rane under the supervision of Merrill Hiscock. The authors wish to thank Bruno Breitmeyer, Paul Cirino, Paul Massman, and Michael Watkins for their contributions to the manuscript as dissertation and thesis committee members.